锥阀典型面密封结构空化喘振数值仿真研究  

Cavitation Surge Numerical Simulation of Surface-sealed Structure of Poppet Valves

作　　者：刘钊[1] 刘禹明 陆亮[1] 孙波 LIU Zhao;LIU Yu-ming;LU Liang;SUN Bo(School of Mechanical Engineering, Tongji University, Shanghai 200092)

机构地区：[1]同济大学机械与能源工程学院,上海200092

出　　处：《液压与气动》2022年第6期72-81,共10页Chinese Hydraulics & Pneumatics

基　　金：国家重点研发计划(2019YFB2005102);国家自然科学基金(52075387);流体动力与机电系统国家重点实验室开放基金(GZKF-201907)。

摘　　要：针对锥阀典型面密封结构中的空化流场进行了数值仿真研究,基于LES湍流模型、mixture多相流模型与Schnerr-Sauer空化模型,研究复现了阀口大尺度空穴。研究表明:面密封结构易导致流束内收缩效应,形成流束外扩与阀座壁面贴合的固定漩涡,进而诱导固定空化的形成。固定空化在恒定的入口压力条件下表现出尺度周期交变的喘振特性。出口压力条件不改变空化喘振频率,但出口压力越小喘振幅值越大。开度增大导致空化尺度先增大后减小,故喘振幅值先升高再下降;同时导致空化发育速度变慢,喘振频率下降。可依据对喘振特性的预测设置蓄能装置,实现更优的空化喘振削弱效果。In this paper,a numerical simulation study of the cavitation flow field in a typical face seal structure of a poppet valve is carried out.Based on the LES turbulence model,the mixture multiphase flow model and the Schnerr-Sauer cavitation model,the large-scale cavitation at the notch is reproduced.The research shows that the surface-sealed structure can easily lead to flow internal vena contracta.A fixed vortex is formed where the outward expansion of the flow beam is in contact with the wall surface of the valve seat.This in turn induces the formation of fixed cavitation.Fixed cavitation exhibits periodically alternating surge characteristics in scale under constant inlet pressure conditions.The outlet pressure condition does not change the cavitation surge frequency.But the smaller the outlet pressure is,the larger the surge amplitude is.The increase of the opening degree causes the volume of the cavitation to increase first and then decrease,so the value of the surge amplitude first increases and then decreases.At the same time,the speed of cavitation development changes,so the surge frequency decreases.The energy storage device can be set according to the prediction of the surge characteristics to achieve a better cavitation surge reduction effect.

关 键 词：锥阀 面密封结构 空化喘振 数值模拟 

分 类 号：TH137[机械工程—机械制造及自动化]